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Stuntman Sailendra Nath Roy's ziplining ponytail stunt death was a result of his hair catching in a pulley while he attempted to break his own distance world record. He suffered a heart attack while suspended next to the Coronation Bridge over the Teesta River in West Bengal. Youtube

Sailendra Nath Roy, a Guinness World Record holder for the longest distance traveled on a zip line while hanging by one's hair, died of a heart attack yesterday while trying to break his own record with a repeat ponytail stunt over a river crossing in India.

Roy, a 48-year-old police officer in West Bengal, meant to cross a zip wire 70 feet above the Teesta River in Darjeeling suspended only by his hair, reported the BBC. The 600-foot-long wire ran parallel to the Coronation Bridge, where an expectant crowd of hundreds became unwitting witnesses to the ponytail stunt death.

The stuntman's long hair was attached to a pulley on the wire, according to the Daily Mail, and he wore a lifejacket in case he fell into the Teesta River.

Roy also wore two billowing banners displaying his regional pride: an Indian flag, and a political banner that read "East Bengal is the Real Power."

He had traveled halfway across the river when his ponytail caught in the wheel. Roy struggled frantically to free himself so he could keep crossing the river using his hands, to no avail.

"He was desperately trying to move forward. He was trying to scream out some instruction. But no one could follow what he was saying. After struggling for 30 minutes he became still," Balai Sutradhar, a photographer covering the event, told the BBC.

There were no doctors or emergency personnel on hand, and police later told local news media that the event had not been formally registered.

Roy was left hanging by his ponytail for almost 45 minutes before rescuers were finally able to retrieve him, reported the Daily Mail. By the time he was admitted to a hospital, doctors declared that a "massive heart attack" was the cause of death.

An autopsy is expected today, reports Sky News. It's unclear whether Roy had a history of heart disease, which predisposes people to heart attacks. The release of hormones like adrenaline in moments of severe stress, as Sailendra Nath Roy undoubtedly experienced in his final moments, can increase risk of cardiac arrest.

Several spectators at the Teesta River recorded Roy's attempt at the stunt. This video stops soon after Roy's ponytail was caught in the pulley, and viewers should be warned that the sight of him struggling to free himself is disturbing:

Roy thrived on the strength of his hair. In 2011, he was awarded a Guinness World Record for crossing a 271-foot zip line via ponytail at the Neemrana Fort in Rajasthan, India.

In 2012, he dragged a 40-ton train on the Darjeeling Himalayan Railway for eight feet with his ponytail.

"We were proud of his bravery," Roy's younger brother Benoy, who was watching his brother's feat for the first time, told Sky Newsabout the ponytail stunt death.

An anonymous friend of Roy's was more ambivalent. "His wife used to urge him to quit doing dangerous stunts," he told the BBC. "Mr. Roy convinced her that crossing the Teesta river would be his last. Unfortunately, that became his last stunt."